Pregnancy Induced Hypertension (PIH) and Pre eclampsia A. Discussion of disease/condition 1. Incidence Pregnancy Induced Hypertension (PIH) is a multi-organ disease process that develops as a result of pregnancy and regresses in the postpartum period. It usually develops after 20 weeks of gestation in a woman who had normal blood pressure. It is defined as an elevation of systolic and diastolic pressures equal to or above 140/90 mm Hg. In clinical practice, the terms PIH and pre eclampsia are used interchangeable, but in pre eclampsia the woman also has protein in her urine indicating that there is renal involvement as well.
The only know cure for pre eclampsia is delivery of the fetus. It is a relatively common problem of pregnancy and affects about 8% of all pregnancies. (Murray, p680) 2. Risk factors There are many factors that increase a woman’s risk. Those include women who are having their first baby, those under 17 years old, women who are obese, having diabetes mellitus, chronic hypertension, or pre-existing vascular disease and women with multi-fetal gestation. Also a woman is more likely to have pre eclampsia if the mother or sister has the disorder. (Murray, p681) 3.
Etiology and Pathophysiology Pre eclampsia is due to generalized vasospasm. In natural pregnancy, vascular volume and cardiac output increase significantly, but despite these increases, blood pressure does not rise in normal pregnancy. This is because pregnant women resistance to the effects of vasoconstrictors such as angiotension. However, in pre eclampsia, peripheral vascular resistance increase because some women are sensitive to angiotension Vasospasm decrease the diameter of blood vessels which results in endothelia cell damage, impeded blood flow and elevated blood pressure.
As a result of this circulation to all body organs, including the kidneys, liver, brain and placenta, is decreased. This will cause many changes such as decreased venal perfusion, glomerular damage, impaired liver function, small cerebral haemorrhages, pulmonary oedema, and dyspnoea and decreased placental circulation. Decrease placental circulation can result in infarctions that increase the risk for abruptio placentae. Also when maternal blood flows hrough the placenta is decreased, the fetus is likely to experience intrauterine growth restriction and persistent fetal hypoxemia and acidosis (Murray, p679-681) 4. Signs and Symptoms Hypertension, generalized oedema and proteinuria are the three classic signs of pre eclampsia. The first sign is that a pregnant woman may notice is oedema and a rapid weight gain which are due to fluid retention. Hypertension is defined as sustained blood pressure equal to or above 140/90.
Blood pressure should be taken in the sitting position with the arm supported in a horizontal position at hear level. Proteinuria usually develops later than hypertension an oedema. The combination of proteinuria and hypertension indicates a worsening disease process. Additional signs include vascular constriction and narrowing of small arteries (e. g. when the retina is examines). Deep tendon reflexes may be very brisk (hyperreflexia) and clonus may be present. This may suggest cerebral irritability. Pre eclampsia is dangerous for the woman and fetus for 2 reasons.
The first reason it develops and progresses so rapidly and secondly the earliest manifestation are not noticed by the woman. Certain symptoms are not noticed by the woman. Certain symptoms include headache, drowsiness, or mental confusion indicate poor cerebral perfusion and may be precursors indicate arterial spasms and oedema in the retina. Numbness or tingling of the hands or feet also happens when nerves are compressed or “upset stomach” are particularly ominous because they indicate distension of the hepatic capsule and often warn that a seizure is imminent.
Decreased urinary output indicates poor perfusion of the kidneys and may precede acute renal failure. (Murray, p682-683). 5. Medical and Nursing Management The only cure for pre eclampsia is delivery of the baby. Home care is possible for many women if the condition is mild and in stable condition with a reassuring fetal status. She must be able to adhere to a prescribed treatment plan which may include bed rest and home blood pressure monitoring. Also, she has to visit the physician twice a week.
She must also do fetal surveillance such as daily kick counts. If the disease is severe that is when blood pressure is higher than 160/110 mmHg proteinuria is higher than 5 gm, and oliguria occurs (500ml or less in 24 hours), then the woman is hospitalized. If it is very severe, the baby is delivered, regardless of gestation, because of comprised placental circulation. Goals of management are to increase placental blood flow, fetal oxygenation and to prevent seizures and other maternal complications such as stroke so she is stabilized before delivery.
For bed rest, the woman is placed on her lateral position and her environment is kept quiet. External stimuli such as lights and noise that may precipitate antihypertensive drugs are used; the fetal rate must be closely monitored because a sudden drop in maternal blood pressure may precipitate fetal distress. Example of some drugs are Hydralazine (Apresoline), nifedipine (Procardia) or labetalol (Normodyne). The anticonvulsant medication given in the USA is magnesium sulphate (MgSo). It prevents seizures and precipitate seizures.
A paediatrician, neonatologist or neonatal nurse must be available to care for the newborn at birth. The next day, proper pre-natal care with attention to pattern weight gain and monitoring of blood pressure and urinary protein may lessen maternal and fetal morbidity and mortality by allowing early detection of the problem. (Murray, p685). When given MgSo, the nurse determines the woman’s respiratory rate hourly, level of consciousness and reflexes). Urine is checked for protein every four hours. She should assess the woman’s stress level and help her with ways to lessen it.
Signs that the woman is recovering from pre eclampsia include urinary output of 4-6 litre/day, decreased or no protein in urine and a return of normal blood pressure within 2 weeks. (Murray, p. 685) B How does your patient fit this textbook picture? My patient, LC, fit this textbook picture in many ways. Theses include this is her first baby, she is obese, have diabetes mellitus (on her 14th week of pregnancy). She also had protein in her urine on 10/09/03 and her BP was 145/90 and so she was diagnosed with PIH and told to stay on her bed rest at home. On 10/09/03, she was diagnosed with pre eclampsia.